Technical Abstract:
Species of the cosmopolitan entomopathogenic form genus Metarhizium play important ecological roles by regulating arthropod populations and recycling insect biomass. The ubiquity of Metarhizium species and their broad host range have made them an attractive alternative to chemical pesticides. Despite commercial interest in the genus and its widespread occurrence, species delimitation, intrageneric relationships, and placement within the Clavicipitaceae remain undefined. Historically, two species and a single variety were accepted in the genus. However, in a recent molecular phylogenetic study 10 lineages (i.e., species and varieties) were proposed. The purpose of this study is to, 1) determine if Metarhizium is monophyletic, 2) identify its sister lineage within Clavicipitaceae, 3) resolve phylogenetic species and infer intrageneric relationships. A multilocus dataset (EF1-alpha, RPB1, beta-tubulin and RPB2) supports the monophyly of Metarhizium and its close association with the largely plant associated members of Clavicipitaceae (subfamily Clavicipitoideae). In addition, a minimum of 12 distinct lineages has been resolved, exceeding prior estimates of diversity in the genus.